Sunil Thapa was a supporting actor who worked across Nepali, Hindi, and Bhojpuri cinema, appearing in over 300 Nepali films. He began his career as a model in Mumbai in 1974 before getting his first major break with the Bollywood film Ek Duuje Ke Liye (1981). He went on to feature in films such as Aaj Ki Awaz (1984), Shapath (1984), Albela (1986), Manav Hatya (1986), Manu The Great (1989), Naseebwaala (1992), Humshakal (1992), and Mary Kom (2014). In 2025, he also appeared in Manoj Bajpayee’s web series The Family Man 3.

Widely recognized for his villainous roles in Nepali cinema, Thapa won several awards, including the Motion Pictures Award Nepal twice, and later served as the chairman of the Everest Film Academy. He passed away due to cardiac arrest in Kathmandu on February 6, 2026, at the age of 68.